Li Jingang, Yang Rundi, Rho Yoonsoo, Ci Penghong, Eliceiri Matthew, Park Hee K, Wu Junqiao, Grigoropoulos Costas P
Laser Thermal Laboratory, Department of Mechanical Engineering, University of California, Berkeley, California94720, United States.
Physical & Life Sciences and NIF & Photon Sciences, Lawrence Livermore National Laboratory, Livermore, California94550, United States.
Nano Lett. 2023 Feb 22;23(4):1445-1450. doi: 10.1021/acs.nanolett.2c04790. Epub 2023 Jan 25.
Carrier distribution and dynamics in semiconductor materials often govern their physical properties that are critical to functionalities and performance in industrial applications. The continued miniaturization of electronic and photonic devices calls for tools to probe carrier behavior in semiconductors simultaneously at the picosecond time and nanometer length scales. Here, we report pump-probe optical nanoscopy in the visible-near-infrared spectral region to characterize the carrier dynamics in silicon nanostructures. By coupling experiments with the point-dipole model, we resolve the size-dependent photoexcited carrier lifetime in individual silicon nanowires. We further demonstrate local carrier decay time mapping in silicon nanostructures with a sub-50 nm spatial resolution. Our study enables the nanoimaging of ultrafast carrier kinetics, which will find promising applications in the future design of a broad range of electronic, photonic, and optoelectronic devices.
半导体材料中的载流子分布和动力学通常决定着它们的物理性质，而这些性质对于工业应用中的功能和性能至关重要。电子和光子器件的持续小型化要求具备在皮秒时间尺度和纳米长度尺度上同时探测半导体中载流子行为的工具。在此，我们报道了在可见-近红外光谱区域的泵浦-探测光学纳米显微镜，用于表征硅纳米结构中的载流子动力学。通过将实验与点偶极子模型相结合，我们解析了单个硅纳米线中与尺寸相关的光激发载流子寿命。我们进一步展示了在硅纳米结构中具有低于50 nm空间分辨率的局部载流子衰减时间映射。我们的研究实现了超快载流子动力学的纳米成像，这将在未来广泛的电子、光子和光电器件设计中找到有前景的应用。
